PHARM - Drugs Affecting the Respiratory System: Asthma - Week 7 Flashcards
Define athsma.
A heterogenous disease of chronic airway inflammation
List 4 symptoms of athsma.
Wheezing
Breathlessness
Chest tightness
Cough
What is the prognosis of athsma like?
Generally good with proper management and treatment compliance
Give three host factors that influence the development of athsma.
Genetics
Gender (females more)
Obesity
Name 6 possible environmental factors that can influence athsma development.
Indoor allergens Outdoor allergens Chemical irritants Tobacco smoke Air pollution Respiratory infections
Breifly explain the pathogenesis of athsma (7).
Allergens are taken up by APCs, which activate Th2 cells, which activate mast cells, which produce IgE.
Mast cells with IgE that bind the allergen release mediators of bronchospasm, mucus, and vascular leaks.
Define allergic athsma.
Airway obstruction due to chronic eosinophilic airway inflammation.
What happens to bronchial blood vessels with athsma and what does it result in (2)?
Blood vessels are leaky and dilated.
Results in airway mucosal oedema and swelling.
What happens to mucus production with athsma? What does this result in?
Hypersecretion. Results in the occlusion of the airway lumen.
Name the three key components of allergic athsma pathogenesis and whether they are well/poorly understood.
Induction phase - poorly understood, related to acquisition of allergy
Smooth muscle shortening - well understood
Inflammation - not completely understood
Name one way to prevent or reverse airway obstruction in athsma.
Treating the smooth muscle contraction which is relatively easy.
Describe one way to prevent or reverse airway inflammation.
Inflammation is partially sensitive to glucocorticoids (corticosteroids)
Name two relaxant agents of the airway smooth muscle.
Adrenaline
B2 adrenoceptor agonists
Name threeconstrictor agents of the airway smooth muscle.
Histamines
Leukotrienes
Acetylcholine
What is the main mechanism of action of B2 agonists in athsma treatment?
Relaxes smooth muscle cells by decreasing cytoplasmic Ca2+
Define SABAs, what kind of substance it is, what kind of treatment it is, whether it is fast or slow acting, and how long it lasts.
Short-acting B-adrenoceptor agonist Is a reliever Mainstay of acute bronchodilator therapy Rapid action (2-5m) Lasts 2-4h
Name 3 adverse effects of SABAs.
Tremors
Palpations
Headache
Explain drug delivery to the lungs.
Using an MDI, 10-20% is inhaled to the lungs and goes directly to systemic circulation.
80-90% is swallowed, and absorbed into the GI tract, going to the liver first.
Define LABAs, what kind of treatment it is, what it must always be combined with, and an additional benefit over other treatment for athsma.
Long-acting B2-adrenoceptor agonists
Is a preventer
Always combined with a glucocorticoid
Has the benefit of chronic bronchodilation
Describe briefly what happens in aspirin-induced athsma and what drug is used to treat it.
Overproduction of LTs
cysteinyl-leukotriene receptor antagonists are used.
How do glucocorticoids prevent/reverse inflammation?
They decrease inflammatory gene expression
Are glucocorticoids fast or slow acting?
Slow onset of action
When are glucocorticoids used and how is it administered (2)?
Used as a first line therapy for prevention
Inhaled or taken orally
Name four side effects of inhaled glucocorticoids.
Hoarseness
Weakness of voice (dysphonia)
Atrophy of vocal cords
Oral thrush
How can the side effects of inhaled glucocorticoids be reduced?
Mouthwash
What should be done with chronic use of oral glucocorticoids and to prevent what?
Taper dose to prevent withdrawal
Name 4 side effects of oral glucocorticoids.
Hypertension
Weight gain
Diabetes
Osteoporosis
